Adjustable wheelchair

ABSTRACT

A wheelchair having a seat frame and at least one side frame is provided. The seat frame includes, for example, a first distal portion having a first releasable attachment and a second distal portion having a second releasable attachment. The at least one side frame includes, for example, a first portion having a substantially horizontal section and second portion having a substantially vertical section. The first releasable attachment of the seat frame is attachable to the side frame substantially horizontal section at a plurality of positions and the second releasable attachment of the seat frame is attachable to the side frame substantially vertical section at a plurality of positions to adjust the position of seat frame.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Provisional U.S. Patent Application Ser. No. 60/481,896, filed Jan. 14, 2004 and titled “Wheelchair,” which is hereby fully incorporated by reference.

BACKGROUND

Wheelchairs provide an important means of transportation for many people. In addition to transportation, wheelchairs also provide a means for recreation. Recreation wheelchairs include wheelchairs suitable for playing tennis, basketball, softball, hockey, table tennis, and many other sports and activities.

SUMMARY

In one embodiment, a wheelchair having a seat frame and at least one side frame is provided. The seat frame includes, for example, a first distal portion having a first releasable attachment and a second distal portion having a second releasable attachment. The at least one side frame includes, for example, a first portion having a substantially horizontal section and second portion having a substantially vertical section. The first releasable attachment of the seat frame is attachable to the side frame's substantially horizontal section at a plurality of positions and the second releasable attachment of the seat frame is attachable to the side frame's substantially vertical section at a plurality of positions to adjust the position of seat frame on the side frame.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of one embodiment of a wheelchair;

FIG. 2A is an exploded view of one embodiment of a releasable attachment assembly; FIG. 2B is a partial perspective view showing the releasable attachment assembly of FIG. 2A attached a wheelchair;

FIGS. 3A, 3B, and 3C illustrate a second embodiment of a releasable attachment assembly; FIG. 3D illustrates a partial perspective view showing the releasable attachment assembly of FIGS. 3A-3C on a wheelchair;

FIG. 4 is a side elevation view of one embodiment of an axle tube releasable attachment assembly;

FIGS. 5A and 5B illustrate one embodiment of a rear seat-to-floor height adjustment;

FIGS. 6A and 6B illustrate one embodiment of a front seat-to-floor height adjustment;

FIGS. 7A and 7B illustrate one embodiment of a center-of-gravity adjustment;

FIGS. 8A, 8B, and 8C are partial perspective view of various embodiments of front end configurations.

DESCRIPTION

The following includes definitions of exemplary terms used throughout the disclosure. Both singular and plural forms of all terms fall within each meaning:

“Attachment” as used herein includes, but is not limited to, something that directly or indirectly attaches one thing to another including, for example, a tie, band, fastener, clamp, or pin.

“Substantially horizontal” as used herein includes, but is not limited to, being largely but not wholly: in the plane of a horizon or primary axis; of, relating to, or near the horizon; or parallel to or in the plane of the horizon; at right angles to a vertical line. “Substantially horizontal” as used herein also includes, but is not limited to, being wholly: of, relating to, or near the horizon; parallel to or in the plane of the horizon; or at right angles to a vertical line. “Substantially horizontal” further includes, but is not limited to, angular deviations up to and including 45 degrees from a horizontal line or axis.

“Substantially vertical” as used herein includes, but is not limited to, being largely but not wholly: perpendicular to the plane of the horizon or to a primary axis; upright; or located at right angles to the plane of a supporting surface. “Substantially vertical” as used herein also include, for example, being wholly: perpendicular to the plane of the horizon or to a primary axis; upright; or located at right angles to the plane of a supporting surface. “Substantially vertical” further includes, but is not limited to, angular deviations up to and including 45 degrees from a vertical line or axis.

“Attach” or “couple” as used herein includes, but is not limited to, directly or indirectly fastening, securing, joining, connecting, affixing, appending, adding, or binding two or more things or components together.

Referring now to FIG. 1, a side elevational view of one embodiment of a wheelchair 100 is shown. Wheelchair 100 includes a seat frame 101 having an L-shaped section 102 and a backrest section 103. L-shaped section 102 includes a plurality of apertures 122 that provide for, among other things, front seat-to-floor height adjustment. A first releasable attachment assembly 112 is coupled to a forward portion of the seat frame 101 and a second releasable assembly 116 is coupled to a rearward portion of the seat frame 101. A crossbar 122 joins a second similar configured portion of the side frame 101. A seat cushion 118 is configured to rest on seat frame 101 so as to provide support to a user. Backrest 103 may be an adjustable backrest that can tilt with respect to L-shaped section 102 of the seat frame to thereby vary the angle between the two components. A backrest cushion 120 may also be provided on backrest 103.

Wheelchair 100 also includes side frame 104. Side frame 104 has a substantially L-shaped configuration that includes a forward section having projections 106 and at least a portion of substantially horizontal section 105. Seat frame 104 also has a rearward portion that includes at least a portion of substantially vertical section 108. A second substantially horizontal section 107 connects sections 105 and 108. An axle tube 109 connects to side frame 104 a second side frame substantially similar in configuration to side frame 104. An axle tube releasable attachment assembly 110 is provided that attaches axle tube 109 to the side frames. A drive wheel 114 is attached to the axle tube. Front and rear caster wheels are also provided on wheelchair 100.

Illustrated in FIG. 2A is an exploded view of one embodiment of the first releasable attachment assembly 112. The assembly 112 includes, for example, a screw 202, coped washers 204, half clamps 206 and 208, and a ferrule nut 210. Half clamp 206 includes a projecting flange 216 that mates with recess 218 in half clamp 208 thereby connecting one end of each of the half clamps. The half clamps are retained in position on their other ends when screw 202 and nut 210 are fastened together. So configured, spaces 212 and 214 of the half clamps form a space in which side frame section 105 is captured. The spaced formed by coped washers 204 captures seat frame section 102 through at least one of apertures 122, which also allows seat frame section 102 to pivot with respect to side frame section 105. FIG. 2B illustrates a partial perspective view showing releasable attachment assembly 112 attached to the seat frame's section 102 and the side frame's section 105. The loosening of screw 202 and nut 210 allows the first releasable attachment assembly 112 to slideably adjust its position along the side frame's section 105. This adjustment modifies the forward position of the seat frame on the side frame. Tightening screw 202 and nut 210 together firmly attaches the assembly 112 to the side frame section 105. The slideable adjustment provides a plurality of positions for attachment.

Referring now to FIGS. 3A, 3B, and 3C, one embodiment of the second releasable attachment assembly 116 is shown. The assembly 116 includes a flange 302 and a body 306. Flange 302 has an aperture 304 for accepting a fastening that pivotably connects assembly 116 to the seat frame 102. Body 306 mates with a half clamp 312. Specifically, body 306 has an aperture 308 at one distal portion and a projecting flange 312 at a second distal portion. Projecting flange 312 mates with recess 318 of half clamp 312 to thereby connect together one end of assembly 116. A screw 318 and ferrule nut 320 are used to connect the second end of assembly 116 together. In particular, body 306 has an aperture 308 that co-locates with an aperture in half clamp 312. The screw 318 and ferrule nut 320 are inserted through the apertures and tightened to connect the second end of assembly 116. When connected, spaces 310 and 314 capture side frame section 108.

FIG. 3D illustrates a partial perspective view showing releasable attachment assembly 116 attached to the seat frame and the side frame. The loosening of screw 318 and nut 320 holding assembly 116 together allows the assembly 116 to slideably adjust its position along side frame's section 108. This adjustment modifies the seat frame height position on the side frame. Tightening screw 318 and nut 320 together firmly attaches assembly 116 to the side frame's section 108. The slideable adjustment provides a plurality of height positions for attachment.

FIG. 4 is an elevational view of one embodiment of axle tube releasable attachment assembly 110. Assembly 110 has a first half clamp 402 and a second half clamp 404. Half clamps 402 and 404 are connected together at one end by a pivot joint 406. The other end of half clamps 402 and 406 are connected together via one ore more screws 408, which are received in apertures of the half clamps. When connected, the half clamps 402 and 408 for a space 410 for capturing substantially horizontal section 107 of the side frame. The assembled clamp is loosened and tightened by turning screw or fastener 408. When loosened, assembly 110 can slideably move along section 107 of the side frame to adjust the axle tube's relative positioning thereon.

FIGS. 5A and 5B illustrate one embodiment of a rear seat-to-floor height adjustment for wheelchair 100. FIG. 5A illustrates a higher position and FIG. 5B illustrates a lower position. The relative difference in height between the two positions is indicated at 502. In one embodiment, rear seat-to-floor height adjustments can be made by loosening the screw and nut of the rear releasable attachment assembly 116 and slideably moving assembly 116 to the desired position on substantially vertical section 108 of the side frame. Once at the desired position, the screw and nut of the releasable attachment assembly 116 is tightened to secure the position.

In another embodiment, rear seat-to-floor height adjustment can be made by loosening both the forward releasable attachment assembly 112 and rearward releasable attachment assembly 116. As mentioned above, loosening rearward releasably attachment assembly 116 allows for adjusting the position of the rear of the seat frame on the substantially vertical section 108 of the side frame. Loosening forward releasable attachment assembly 112 allows for adjusting its position on the side frame's section 105. Positional adjustment of forward and rearward releasable attachment assemblies 112 and 116 may be necessary to effectuate the complete range of rear seat-to-floor adjustments. Positional adjustment of both assemblies 112 and 116 compensates for the substantially vertical adjustment of rear assembly 116 on side frame section 108. In embodiments where the side frame's substantially vertical portion 108 is arcuate, loosening and tightening of the forward releasable attachment assembly 112 may not be necessary to effectuate the complete range of rear seat-to-floor height adjustment.

FIGS. 6A and 6B illustrate front seat-to-floor height adjustment of wheelchair 100. FIG. 6A illustrates a higher front seat-to-floor height and FIG. 6B illustrates a lower front seat-to-floor height. The respective difference in height is indicated at 602. To adjust the front seat-to-floor height, the screw and nut of the forward releasable attachment assembly 112 is loosened to allow the assembly's position on side frame section 102 to be adjusted. This adjustment is made by changing the aperture 122 through which the screw and nut of forward releasable attachment assembly 112 is attached to side frame section 102. Once in the desired aperture is selected, the screw and nut of the forward releasable attachment assembly 112 are tightened to secure the position.

FIGS. 7A and 7B illustrate one embodiment of a center-of-gravity adjustment of wheelchair 100. This adjustment is made by changing the position of axle tube releasable attachment assembly 110 on section 107 of the side frame. FIG. 7A illustrates an adjustment or position where a center-of-gravity of the wheelchair may located behind the axle tube 109. FIG. 7B illustrates an adjustment or position where a center-of-gravity may be located forward of the axle tube 109. A plurality of adjustments between these two positions is also possible such as, for example, placing a center-of-gravity of the wheelchair or wheelchair and occupant directly or substantially directly above the axle tube 109. More specifically, FIG. 7A illustrates a range of possible adjustment of the axle tube 109 between limits 702 and 704. In the embodiment of FIG. 7A, the axle tube 109 is located a distance 706 forward of the rearward limit 702. This position, and positions near thereto, allow the axle tube 109 to be positioned forward of a center-of-gravity of the wheelchair and/or the wheelchair occupant. In the embodiment of FIG. 7B, the axle tube 109 is located more closely to the rearward limit 702 thereby decreasing the distance 706. This position, and positions near thereto, allow the axle tube 109 to be positioned behind the center-of-gravity of the wheelchair and/or wheelchair occupant. Adjustments to the axle tube 109 position on the side frame are accomplished by loosening the axle tube releasable attachment assembly 110. Assembly 110 is then slideably moved along side frame's section 107. When the desired position is attained, assembly 110 is tightened to secure the position on side frame's section 107. Such adjustments may increase the stability of the wheelchair depending on its use and the characteristics of the wheelchair occupant.

FIGS. 8A, 8B, and 8C are partial perspective views of various embodiments of front end configurations of wheelchair 100. FIG. 8A illustrates one embodiment showing mounting projection 106 free of any attachments. FIG. 8B illustrates one embodiment showing a bumper 802 attached to mounting projection 106. Bumper 802 includes a releasable attachment assembly 804 that includes, for example, a C-clamp that captures mounting projection 106 in its inner space and is secured to the mounting projection 106 by a screw or other fastener that tightens the ends of the C-clamp around projection 106. Tightening and loosening of the C-clamp allows bumper 802 to be attached and removed from the mounting projections 106.

FIG. 8C illustrates one embodiment showing a wing 806 attached to mounting projection 106. Wing 806 includes a releasable attachment assembly 808 that also has, for example, a C-clamp that captures mounting projection 106 in its inner space and is secured to the mounting projection 106 by a screw or other fastener that tightens the ends of the C-clamp around projection 106. Tightening and loosening of the C-clamp allows wing 806 to be attached and removed from the mounting projections 106. The bumper 802, wing 808 and other similar-type attachments serve to protect the wheelchair user's legs from contact with objects, including other wheelchairs, when the wheelchair is used for sports or other active recreational activities.

While the present invention has been illustrated by the description of embodiments thereof, and while the embodiments have been described in considerable detail, it is not the intention of the applicants to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. For example, seat frame or side frame sections can be curved or arcuate in shape and clamps can have various geometries and shapes without changing their functions. Therefore, the inventive concept, in its broader aspects, is not limited to the specific details, the representative apparatus, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the applicant's general inventive concept. 

1. A wheelchair comprising: a seat frame having first and second distal portions, the first distal portion comprising a first releasable attachment and the second distal portion comprising a second releasable attachment; at least one side frame comprising a first portion having a substantially horizontal section and second portion having a substantially vertical section; and wherein the first releasable attachment of the seat frame is attachable to the side frame substantially horizontal section at a plurality of positions and the second releasable attachment of the seat frame is attachable to the side frame substantially vertical section at a plurality of positions to adjust at least a portion of the seat frame's height above a floor.
 2. The wheelchair of claim 1 wherein the first releasable attachment comprises at least one releasable clamp.
 3. The wheelchair of claim 1 wherein the second releasable attachment comprises at least one releasable clamp.
 4. The wheelchair of claim 1 wherein the first and second releasable attachments each comprise at least one releasable clamp.
 5. The wheelchair of claim 1 wherein the side frame comprises third portion for releasably attaching at least one wing or bumper assembly.
 6. The wheelchair of claim 5 wherein the third portion comprises mounting projection.
 7. The wheelchair of claim 5 wherein the third portion comprises a mounting boss for attaching a wing or bumper assembly.
 8. The wheelchair of claim 5 wherein the third portion comprises a substantially cylindrical shape.
 9. The wheelchair of claim 5 wherein the third portion comprises a wing or bumper clamp receiving surface.
 10. The wheelchair of claim 1 wherein the side frame comprises a fourth portion having a substantially horizontal section.
 11. The wheelchair of claim 10 wherein the fourth portion substantially horizontal section comprises an axle tube attachment receiving surface.
 12. The wheelchair of claim 1 further comprising an axle tube and an axle tube attachment and wherein the side frame comprises a fourth portion having a substantially horizontal section having an axle tube attachment receiving surface.
 13. The wheelchair of claim 12 wherein the axle tube attachment is attachable to the axle tube attachment receiving surface at a plurality of positions that adjust a center-of-gravity of the wheelchair.
 14. A wheelchair comprising: a seat frame comprising a substantially L-shaped portion and a backrest portion, the substantially L-shaped portion comprising a front releasable attachment assembly and a rear releasable attachment assembly; a side frame comprising a substantially L-shaped portion having a substantially horizontal section and a substantially vertical section; and the front releasable attachment assembly attachable to the substantially horizontal section at a plurality of positions and the rear releasable attachment assembly attachable the substantially vertical section at a plurality of positions to adjust the seat frame position.
 15. The wheelchair of claim 14 wherein the front releasable attachment comprises at least one releasable clamp.
 16. The wheelchair of claim 14 wherein the side frame further comprises a projecting portion.
 17. The wheelchair of claim 16 further comprising a wing/bumper assembly having at least one releasable attachment assembly that attaches to the wing/bumper assembly to the projecting portion of the side frame.
 18. The wheelchair of claim 16 wherein the substantially horizontal section of the side frame is between the projecting portion and the substantially vertically section of the side frame.
 19. A wheelchair comprising: a first means for supporting at least a portion of a seat; a second means for supporting at least a portion of a seat; a first means for releasably attaching the first and second means for supporting and for slideably adjusting a forward portion of the first means for supporting along a forward portion of the second means for supporting; and a second means for releasably attaching the first and second means for supporting and for slideably adjusting a rearward portion of the first means for supporting along a rearward portion of the second means for supporting.
 20. The wheelchair of claim 19 wherein the first means for releasably attaching comprises a clamp. 